[Aus dem Text:] Spanende Bearbeitung nimmt nach wie vor eine zentrale Stellung ein. Dies gilt nicht nur für die Gegenwart. Die betreffenden Unternehmen prognostizieren mehrheitlich sogar für die spanenden und trennenden Verfahren einen Bedeutungszuwachs. Dieser geht einher mit der eindeutigen Tendenz zu weiter wachsenden Genauigkeitsforderungen an die Fertigungsprozesse der Metall-, Kunststoff- und Elektroindustrie. Die gegenwärtigen und künftigen ökologischen, sozialen und wirtschaftlichen Rahmenbedingungen und gesellschaftlichen Zielstellungen, wie - die Ressourcenschonung – und hier insbesondere die Verbesserung der Energieeffizienz in der Produktionstechnik, - die Befriedigung individualisierter Bedürfnisse – mit dem daraus für die Fertigung folgenden Bedarf an weiterer Flexibilisierung sowie - die immerwährende Forderung nach weiterer Steigerung der Produktivität, führen im Zusammenhang mit der spanenden Genauigkeitsfertigung zu einem sich verschärfenden Zielkonflikt im Dreiecksverhältnis von Energieeinsatz, Genauigkeit und Produktivität bei der spanenden Bearbeitung.

Magnetic Resonance Imaging (MRI) is considered as a slow imaging technique. Various approaches to accelerate MRI imaging have been explored by researchers in the past decades. Earlier gradient based methods have reached the safety limit. Parallel receiving techniques achieve accelerations by reducing phase encoding steps. Among these methods, SEA Imaging achieved the highest possible acceleration by completely eliminating phase encoding. However, SEA imaging is limited to thin planar slices above the array due to the correction needed for the inherent phase cancellation caused by voxel-sized coils. A phase compensation gradient pulse is used for this correction in SEA imaging. This phase compensation is dependent on slice position and thickness as well as the orientation of the array elements, placing stringent restrictions on SEA imaging, limiting its applications. Converting the SEA system into Transmit / Receive (T/R) mode, which is the main purpose of this study, eliminates the requirement for phase compensation gradient because phase departed during transmit is refocused during receiving. Independent amplitude and phase control of RF pulse for each coil of a SEA array is achieved using a low cost scalable parallel transmit system design. The first 64-channel parallel transmitter for MRI in the world is constructed and tested. Software is also developed to control the phase and amplitude of all the 64 channels of RF excitation pulses independently through National Instruments DAQ system. The system consists of vector modulators controlled by digital controlled potentiometers, two-stage amplifiers and T/R switches on the transmit side. All these are combined with newly designed and constructed preamplifiers and the existing 64-channel parallel receivers on the receive side, leading to the only 64-channel parallel T/R system available for MRI. As a bonus, the system can be easily updated to full Transmit SENSE capability. Furthermore, simulations and images are done to synthesize transmit patterns thanks to the large channel count. Testing results show that the system is capable of 100W per channel simultaneous transmission. Using this system, transmit field can be synthesized by varying the phase and amplitude across channel without traditionally required complicated pulse sequences involving simultaneous RF and gradient fields. Curved slice excitation has conventionally been considered a difficult task for MRI, achievable only through complicated pulses sequences. Using this system and flexible array wrapped around the subject to be imaged, the system is able to excite curved slice using one shot. TR images indicate that the system is capable of high speed surface imaging at 200 frames per second following the surface of a flexible SEA array coil which has not been achieved using other methods in MRI.

Made available in DSpace on 2015-03-12T11:47:58Z (GMT). No. of bitstreams: 1 ElinezSR_TESE.pdf: 1138025 bytes, checksum: 344a1e74fd6b942b9e479821ac43ff43 (MD5) Previous issue date: 2014-07-12 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Ecossistemas aqu?ticos recebem elevada quantidade de subs?dios energ?ticos provenientes de fontes al?ctones de detritos e nutrientes. O objetivo deste estudo foi investigar como tais subs?dios interagem com peixes on?voros e afetam a estrutura e din?mica tr?fica de ecossistemas lacustres tropicais. Os efeitos do aporte de detritos al?ctones e da onivoria por peixes filtradores sobre a regula??o das comunidades planct?nicas foram investigados atrav?s de um experimento em 24 mesocosmos, com delineamento fatorial 2x2, onde dois n?veis de detritos (com ou sem aporte) foram combinados com dois n?veis de peixes (presen?a ou aus?ncia) e a resposta do pl?ncton aos tratamentos foi monitorada. Os resultados desse experimento mostram que o aporte de detritos aumentou a concentra??o de nutrientes al?m da biomassa de algas e invertebrados planct?nicos atrav?s da eutrofiza??o dos mesocosmos. No entanto, o efeito positivo do aporte de detritos sobre a biomassa zooplanct?nica foi mais forte na aus?ncia de peixes filtradores. Por outro lado, a presen?a de peixes filtradores reduziu a biomassa zooplanct?nica atrav?s da preda??o e aumentou a biomassa de algas, aparentemente atrav?s da ciclagem de nutrientes. Os efeitos do aporte de nutrientes sobre a estrutura tr?fica dos ecossistemas foi investigada atrav?s da an?lise comparativa de um reservat?rio eutr?fico e outro mesotr?fico, de onde foram amostrados indiv?duos de 13 esp?cies de peixes e seus principais itens alimentares para a an?lise de is?topos est?veis de carbono e nitrog?nio. Os resultados demonstram que a posi??o tr?fica dos peixes foi em geral menor no reservat?rio eutr?fico do que no reservat?rio mesotr?fico. Al?m disso, os resultados de um modelo de mistura sugerem que as fontes pel?gicas de carbono para os peixes foram mais importantes do que as fontes bent?nicas-litor?neas, principalmente no reservat?rio eutr?fico. Portanto, subs?dios al?ctones de detritos e 12 nutrientes alteram a estrutura tr?fica dos ecossistemas lacustres com importantes implica??es para a din?mica desses ecossistemas

Esta dissertação trata do nascimento e evolução do Fundo de Garantia do Tempo de Serviço (FGTS), seu momento histórico, sua evolução, o tratamento constitucional dado ao instituto na Constituição de 1988 e a sua efetividade através da lei 8.036/90. Analisa o tema da proteção do trabalho, demissão sem justa causa, no mundo contemporâneo, com passagens por vários países dentro de um contexto de plena globalização. A proteção do emprego no Brasil como conhecemos, através de um Fundo com natureza jurídica híbrida, com função de direito social do trabalhador no momento de sua despedida e a aplicação dos recursos das contas vinculadas em programas habitacionais, de saneamento ambiental e infraestrutura tornam o FGTS um Fundo de natureza única no mundo todo. Os investimentos realizados com recursos do FGTS são imprescindíveis para o desenvolvimento da economia brasileira, com reflexos diretos na geração de empregos e na melhoria do bem estar social, não só dos trabalhadores filiados ao sistema FGTS, mas a toda população brasileira. A Ação Direta de Inconstitucionalidade 5090/DF trata da inconstitucionalidade do índice de correção do FGTS, a Taxa Referencial (TR), informando que o índice não é apto a representar o fenômeno inflacionário e por isso deve ser considerada sua inconstitucionalidade, por ferir o direito de propriedade (art.5º, XXII, CF), a moralidade administrativa (art. 37, X) e o próprio Fundo de Garantia do Tempo de Serviço (art. 7º, III). A proposta legislativa que encerra o trabalho deve levar em consideração a natureza jurídica polivalente do FGTS, atendendo tanto quanto possível aos interesses dos cotistas do Fundo e ao mesmo tempo os tomadores de empréstimos com recursos do FGTS, não quebrando o equilíbrio econômico financeiro do Fundo. / This dissertation deals with Guarantee Fund for Time of Service (FGTS) origin and evolution, its historical moment, the treatment conferred by Brazilian Constitution of 1988 and the effectiveness provided by the law 8.036/90. It analyses employment protection, unjustified resignation on the contemporary world, according the law of many countries inserted in the context of globalization. Brazilian employment protection policy by means of a hybrid juridical nature fund, the function as laid off worker\'s social right, and investment in housing programs, environmental sanitation and infrastructure projects make FGTS a fund with unique characteristics. FGTS resources investments are indispensable to Brazilian economy development, resulting in job creation and welfare improvement for whole Brazilian population. The Direct Action of Unconstitutionality 5090/DF deals with unconstitutionality of FGTS correction index, called \"referential tax\" (TR), alleging the unfitness of this index in representing the inflationary phenomenon as cause to declare its unconstitutionality, in reason of disagreement with property right (art. 5º, XXIII, CF), administrative morality (art. 37, X), and the Guarantee Fund for Time of Service itself (art. 7º, III). The legislative proposal at the end of this dissertation considers the polyvalent juridical nature of FGTS, attending the interests of fund quotaholders and FGTS resources borrowers, and preserving its economic-financial balance.

As lesões tendíneas são uma das mais comuns que ocorrem nos esportes, sua freqüência é de 10 a 55% de todas as lesões ocorridas. A cabeça medial do músculo gastrocnêmio (GCm) é constituído por duas regiões bem distintas: uma região profunda \"vermelha\" e uma região superficial \"branca\". Dada essa característica de distribuição dos tipos de fibras, torna-se possível determinar se, no mesmo músculo, a tenotomia afeta as fibras de maneira diferente, dependendo do tipo de fibra predominante em cada região. O objetivo deste estudo foi avaliar o efeito da tenotomia e tenorrafia experimental na GCm. Foram usados 38 ratos Wistar machos pesando aproximadamente 300 g divididos em três grupos: Controle (C), Tenotomizado (T) e Tenorrafiado (R), avaliados aos 14 e 21 dias pós-cirurgia. Os animais foram mantidos sob as mesmas condições de alojamento, alimentação, temperatura umidade e luz. No grupo T, o tendão calcâneo do membro pélvico esquerdo foi dissecado e seccionado transversalmente no terço médio. No grupo R, este mesmo tendão foi imediatamente submetido à sutura de Kessler modificada após a tenotomia. Foram realizadas seções de 10 µm de espessura em criostato e, em seguida, estas secções foram submetidas às técnicas da hematoxilina e eosina, picro-sirius, NADH-tr e para análise em microscopia eletrônica de transmissão A significância estatística das diferenças inter-grupos foi determinada pela análise de variância, (ANOVA) e foi aceito p <0,05. Foram encontradas diferenças significativas entre os grupos C, T e R. Observou-se uma grande variação no tamanho e formato das fibras musculares e, ainda, uma desorientação e degeneração das miofibrilas e desorganização dos sarcômeros nos animais do grupo T. Ambos os grupos, T e R, apresentaram diminuição da área de secção transversa e comprimento da GCm. / Tendon injuries are one of the most commonly occurring in sports, its frequency is 10 to 55% of all injuries. The medial head of gastrocnemius muscle (GCm) consists of two clearly distinct regions: a deep region \"red\" and, a superficial region \"white\". Because of that characteristic distribution of fiber types, it becomes possible to determine if the same muscle tenotomy affects differently, depending on the predominant fiber type in each region. The aim of this study was to evaluate the effect of experimental tenotomy and tenorrhaphy on GCm. We used 38 male Wistar rats weighing approximately 300 g divided into three groups: control (C), tenotomized (T) and Tenorraphized (R). They were evaluated at 14 and 21 days after the surgery. Animals were kept under the same conditions of accommodation, feeding, temperature, humidity and light. In T group, calcaneal tendon of the left pelvic limb was dissected and sectioned in the middle third. In R group, the same tendon was immediately submmitted to the modified Kessler suture after tenotomy. Sections were performed in 10 µm thick in a cryostat and they were then stained according to hematoxylin and eosin, Picrosirius, NADH-tr methods and they were analyzed by transmission electron microscopy. The statistical significance of inter-group differences was determined by analysis of variance (ANOVA) and was accepted p<0.05. Significant differences were found between C, T and R groups. There was a wide variation in size and shape of muscle fibers and also a disorientation and degeneration of myofibrils and disorganization of sarcomeres in T group. Both T and R groups showed a decrease in cross-sectional area and length of the GCm.

A solução da maioria dos problemas práticos enfrentados por administradores financeiros passa pela identificação prévia do custo de oportunidade para investimentos de diferentes prazos e riscos. Este trabalho busca, no conjunto de seus capítulos, realizar uma avaliação crítica das propriedades da estrutura temporal de taxas de juros em reais e de sua utilização como variável exógena fundamental na análise financeira. Sem a pretensão de esgotar qualquer dos temas abordados, procurou-se estabelecer a curva de juros para investimentos livres de riscos em moeda nacional e, através de um conjunto de testes empíricos e observações informais de séries de dados de mercado, identificar peculiaridades que possam invalidar a implementação no Brasil de modelos desenvolvidos no contexto internacional. Dados os aspectos característicos do mercado doméstico evidenciados nos estudos, foram apresentados modelos explicativos tanto para a formação das taxas prefixadas de período quanto para a determinação da remuneração de operações financeiras indexadas à taxa referencial TR. / The solution to most of the problems facing financial managers requires prior identification of the cost of money for different maturities and risks. This paper aims, in its overall content, to examine the Brazilian currency yield curve’s properties and its supporting role in financial analysis. With no intention of exhausting any of the tackled subjects, the Real risk-free term structure was defined and a set of empirical tests performed to identify, with the support of additional data observation, local market’s peculiarities that might prevent international models from being accurately applied in Brazil. Given the domestic market’s distinguishing features emphasized in the studies, models were proposed to explain how short term interest rates are determined in the marketplace for derivatives, and to allow the pricing of financial instruments indexed to the so called TR benchmark (Taxa Referencial).

Ce manuscrit présente les travaux de thèse réalisés dans le cadre d’une convention CIFRE entre Renault Trucks et le LMFA. Une stratégie de contrôle d’écoulement, associant un volet déflecteur et des actionneurs de type jets pulsés et synthétiques, est étudiée expérimentalement en vue de réduire la traînée aérodynamique de corps non profilés à culot droit. Une première approche consiste à étudier l’influence de cette stratégie sur une maquette bidimensionnelle. Des mesures de vitesse dans le sillage proche par TR-PIV et par anémométrie à fil chaud démontrent qu’une certaine gamme de fréquence d’actionnement permet à l’écoulement de recoller sur le volet et de diminuer les fluctuations de vitesse dans la zone de recirculation, ce qui engendre une augmentation de la pression au culot. Une analyse par moyenne de phase et la détermination de corrélations spatio-temporelles permettent d’identifier les perturbations induites par le contrôle conduisant à ces modifications de l’écoulement. Un système de jets synthétiques est ensuite intégré à une maquette simplifiée de véhicule poids lourd à l’échelle 1/8e, dont le sillage est représentatif des remorques réelles. Des gains en traînée significatifs sont obtenus et sont associés aux mêmes phénomènes aérodynamiques que pour la maquette bidimensionnelle. Enfin, une étude paramétrique montre la robustesse du contrôle aux caractéristiques de la couche limite incidente aux jets et à la longueur du volet déflecteur. / This document presents the research work realized in the scope of a PhD thesis with Renault Trucks and the LMFA. A flow control strategy, combining an inclined flap with pulsed or synthetic jets, is experimentally studied to reduce the aerodynamic drag of square-back bluff bodies. A first approach consists in studying the effect of this strategy on the flow behind a twodimensional model. The near-wake flow is characterized by the use of velocity measurements obtained by Time-Resolved Particles Image Velocimetry and hot-wire Anemometry. These measurements show that the increase in rear base pressure, obtained in a specific range of actuation frequencies, is associated with the reattachment of the flow on the flap and with a decrease in velocity fluctuations within the recirculation area. A phase average analysis and the determination of space-time correlations allow identifying the aerodynamic disturbances induced by the control system and leading to these modifications of the wake flow. A synthetic jet system is integrated to a 1 :8 scale simplified truck model, with a wake flow similar to this of real trailers. Significant drag reductions are obtained using active control and are associated with the same flow phenomena as these observed in the two-dimensional model study. Eventually, a parametric study is performed and shows the robustness of the flow control strategy to the characteristics of the boundary layer developing on the model roof and to the flap length.

Les récepteurs de l’ocytocine (OTR) et de la vasopressine (AVPR) sont connus pour être impliqués dans la modulation d’effets centraux complexes. Récemment l’OTR a été proposé comme une cible thérapeutique pour le traitement des troubles du spectre autistique (TSA).Afin de mieux comprendre le rôle de l’OTR et des AVPR dans les TSA, d’éclaircir des nouveaux traits de sa pharmacologie et d’établir des méthodes du criblage sur les récepteurs sauvages, nous avons développé des traceurs pour la tomographie par émission des positons ainsi que des sondes fluorescentes pour la famille OT/AVP des RCPG. Les ligands fluorescents ont été utilisés pour établir un test de liaison TR-FRET pour l’OTR et pour initier le développement du test alternatif sur les récepteurs sauvages. Les radiotraceurs TEP seront bientôt testés chez la souris et chez le singe pour évaluer leurs performances pour la détection des récepteurs de l’ocytocine centraux avant d’envisager des études chez l’Homme. / In order to better understand the role of OTR and AVPR in ASD, to reveal new features in its pharmacology and signaling and to establish high-throughput screening method on wild-type G protein-coupled receptors, we developed imaging probes for the oxytocin-vasopressin receptors family, namely radiotracers for positron emission tomography and optical probes for fluorescence detection and imaging. The fluorescent ligands have been used to establish TR-FRET binding assay for OTR and to initiate the development the screening assay for the wild-type oxytocin receptor. The PET radiotracers will be shortly tested in mice and monkeys to evaluate their potency in detecting the central oxytocin receptors.

Die Forschungsarbeiten der 19 Teilprojektes des SFB/TR 96 verfolgen den Ansatz, spanende Werkzeugmaschinen zu Fertigungsqualität und Wirtschaftlichkeit unter den Bedingungen einer energieeffizienten Produktion durch konstruktive und steuerungstechnische Lösungen zu befähigen. Damit besteht das Ziel des SFB/TR 96 in der Lösung des Zielkonflikts von Energieeinsatz, Genauigkeit und Produktivität bei der spanenden Fertigung.

Die Forschungsarbeiten der 19 Teilprojektes des SFB/TR 96 verfolgen den Ansatz, spanende Werkzeugmaschinen zu Fertigungsqualität und Wirtschaftlichkeit unter den Bedingungen einer energieeffizienten Produktion durch konstruktive und steuerungstechnische Lösungen zu befähigen. Damit besteht das Ziel des SFB/TR 96 in der Lösung des Zielkonflikts von Energieeinsatz, Genauigkeit und Produktivität bei der spanenden Fertigung.:Motivation und Überblick Christian Brecher (RWTH Aachen, Sprecher des SFB/TR 96) Erstellung und Abgleich eines strukturbasierten thermischen Modells der kugelgewindegetriebenen Vorschubachse eines Hexapoden Alexander Galant, Steffen Schroeder, Bernd Kauschinger (IWM TU Dresden) Michael Beitelschmidt (IFKM TU Dresden) Wärme im Zerspanungsprozess und ihre Wirkung im Werkzeug Matthias Putz, Gerhard Schmidt, Ulrich Semmler (IWU Chemnitz) Michael Bräunig (IWP TU Chemnitz) Fritz Klocke, Drazen Veselovac, Matthias Brockmann, Thorsten Augspurger, Patrick Mattfeld, Matthias Rasim, Christian Wrobel (Lehrstuhl für Technologie der Fertigungsverfahren RWTH Aachen) Parameteridentifikation in thermo-elastischen Systemen Roland Herzog, Ilka Riedel (Professur für Numerische Mathematik (partielle Differentialgleichungen) TU Chemnitz) Bernd Kauschinger, Steffen Schroeder (IWM TU Dresden) Prognose von Verlustleistungen und Kontaktwärmeübergängen an Maschinenkomponenten Christian Brecher, Marcel Fey, Kolja Bakarinow, Stephan Neus (Lehrstuhl für Werkzeugmaschinen RWTH Aachen) Reinhold Kneer, Yona Frekers (WSA RWTH Aachen) Berechnung von thermo-elastischen Deformationen in Werkzeugmaschinen – Vergleich numerischer Verfahren – Michael Beitelschmidt, Marian Partzsch (IFKM TU Dresden) Peter Benner, Norman Lang (MiIT TU Chemnitz) Andreas Naumann, Axel Voigt, Jörg Wensch (IWR TU Dresden) Analyse der Wärmeentstehung im Antrieb und Temperierung von Strukturen und Antrieben am Beispiel von Werkzeugmaschinen Stefan Winkler, Ralf Werner (EWA TU Chemnitz) Andre Bucht, Welf-Guntram Drossel (Fraunhofer IWU) Jürgen Weber, Juliane Weber (IFD TU Dresden) Immanuel Voigt (IWP TU Chemnitz) Experimenteller Vergleich kennfeld- und strukturmodellbasierter Korrektur Steffen Ihlenfeldt, Christian Naumann (Fraunhofer IWU) Xaver Thiem, Mirko Riedel, Bernd Kauschinger (IWM TU Dresden) Zeitabhängige Beschreibung volumetrischer thermo-elastischer Verlagerungen von Werkzeugmaschinen Christian Brecher, Marcel Fey, Matthias Wennemer (Lehrstuhl für Werkzeugmaschinen RWTH Aachen) Messtechnisch basierte Ansätze zur Korrektur thermischer Verlagerungen Mirko Riedel, Jens Müller (IWM TU Dresden) Michel Klatte, Christian Wenzel (Fraunhofer IPT) Bewertung thermisch bedingter Verlagerungen mit Prüfwerkstücken Hajo Wiemer, Hubert Höfer (IWM TU Dresden)